Pest identification
What's eating my delicata squash?
Squash vine borer (Melittia cucurbitae)
Signs: Sudden wilting of otherwise healthy vines; sawdust-like frass at the base of stems; caterpillars tunnel inside, girdling the vine.
Control: Wrap young stem bases in foil or row cover; time planting to miss peak adult flight (late June–July in most US regions); inject Bt into affected stems; bury vine sections to encourage secondary roots.
Squash bug (Anasa tristis)
Signs: Bronze-colored eggs in clusters on leaf undersides; nymphs and adults suck sap; leaves wilt, yellow, and turn crispy; plants can die.
Control: Crush egg masses daily; hand-pick adults and nymphs into soapy water; lay boards near plants overnight and destroy sheltering bugs in the morning; insecticidal soap for young nymphs.
Cucumber beetle — striped and spotted (Acalymma vittatum / Diabrotica undecimpunctata)
Signs: Feeding holes in flowers and foliage; transmits bacterial wilt (Erwinia tracheiphila) which causes irreversible plant collapse.
Control: Use yellow sticky traps to monitor; row covers until flowering; pyrethrin spray for high populations; remove and destroy wilted plants to break wilt transmission cycle.
Aphids
Signs: Colonies on new growth and undersides; leaves curl; virus transmission (Cucumber mosaic virus) distorts fruit and foliage.
Control: Strong water spray; insecticidal soap; encourage ladybugs and lacewings; reflective mulch repels colonizing aphids.
Keep delicata squash pest-free
Healthy plants resist pests best. Get the basics right:
- What eats squash — the species this cultivar belongs to
- What eats delicata squash — our other guide for the same plant
- What's wrong with my plant? — the diagnosis apps compared
- Common delicata squash problems & fixes
- Delicata Squash watering schedule
- Delicata Squash light requirements
- Full delicata squash care guide
Delicata Squash pests — FAQ
What is eating my delicata squash?
Delicata squash faces the same heavyweight threats as all Cucurbita pepo types. Squash vine borers are the most destructive pest in eastern North America, tunneling into vines and causing sudden wilt. Cucumber beetles spread bacterial wilt. Squash bugs suck sap and kill vines. Powdery mildew on foliage is almost universal late-season.
How do I get rid of squash vine borer (melittia cucurbitae) on delicata squash?
Sudden wilting of otherwise healthy vines; sawdust-like frass at the base of stems; caterpillars tunnel inside, girdling the vine. Wrap young stem bases in foil or row cover; time planting to miss peak adult flight (late June–July in most US regions); inject Bt into affected stems; bury vine sections to encourage secondary roots.
How do I get rid of squash bug (anasa tristis) on delicata squash?
Bronze-colored eggs in clusters on leaf undersides; nymphs and adults suck sap; leaves wilt, yellow, and turn crispy; plants can die. Crush egg masses daily; hand-pick adults and nymphs into soapy water; lay boards near plants overnight and destroy sheltering bugs in the morning; insecticidal soap for young nymphs.
How do I get rid of cucumber beetle — striped and spotted (acalymma vittatum / diabrotica undecimpunctata) on delicata squash?
Feeding holes in flowers and foliage; transmits bacterial wilt (Erwinia tracheiphila) which causes irreversible plant collapse. Use yellow sticky traps to monitor; row covers until flowering; pyrethrin spray for high populations; remove and destroy wilted plants to break wilt transmission cycle.
How do I get rid of aphids on delicata squash?
Colonies on new growth and undersides; leaves curl; virus transmission (Cucumber mosaic virus) distorts fruit and foliage. Strong water spray; insecticidal soap; encourage ladybugs and lacewings; reflective mulch repels colonizing aphids.